High fire rate guns, such as those firing over 200 rounds per minute per barrel, may be used to propel a stream of projectiles at a designated target. Typically, the muzzle velocity and aerodynamic properties of the stream of projectiles are roughly consistent such that the projectiles arrive at any given range at the same linear spacing and in the order in which they were fired. Target movement, gun aiming and ammunition natural dispersion reduce chances that two projectiles will strike a target in the exact same spot. Target damage occurs as the projectiles individually impact the target, and projectiles that fail to impact the target cause it no damage.
It is known that target damage is substantially greater if it is hit simultaneously by several projectiles than if it is hit seriatim by the same number of projectiles. The problem has been to create a barrage or group of projectiles which arrive at the target intentionally and controllably simultaneously.
Previous weapons systems have attempted increased target damage by mimicking the simultaneous arrival of munitions by firing flechette rounds or a pattern of rounds. The flechette round achieves simultaneous arrival by separating smaller, lighter submunitions from the carrier projectile in flight. Lower fire rate, larger caliber weapons have attempted to mimic simultaneous arrival by re-positioning the barrel between rounds in a predetermined pattern. In this instance, the rounds still arrive in the order fired, and depend on fuse action to achieve target kill.